import type { DeviceLogsBackend, HistoryOpts, InternalDeviceLog, LogContext, OutputDeviceLog, Subscription } from '../struct.js';
export declare class LokiBackend implements DeviceLogsBackend {
    private subscriptions;
    private pusher;
    private tailCalls;
    constructor();
    readonly available = true;
    /**
     *
     * Return $count of logs matching device_id in ascending order.
     *
     * The logs are sorted by timestamp since Loki returns a distinct stream for each label combination.
     *
     * @param ctx
     * @param count
     */
    history($ctx: LogContext, { count, start }: HistoryOpts): Promise<OutputDeviceLog[]>;
    publish(ctx: LogContext, logs: Array<InternalDeviceLog & {
        version?: number;
    }>): Promise<any>;
    private push;
    private createTailCall;
    subscribe($ctx: LogContext, subscription: Subscription): Promise<void>;
    unsubscribe($ctx: LogContext, subscription: Subscription): Promise<void>;
    private getDeviceQuery;
    private getKey;
    private getStructuredMetadata;
    private getLabels;
    private fromDeviceLogsToEntries;
    private fromLogEntriesToStream;
}